Blower assembly with pre-swirler

ABSTRACT

A blower assembly for use in a vehicle is disclosed, wherein the blower assembly includes a pre-swirler for causing a change of direction of air entering the blower assembly.

FIELD OF THE INVENTION

The invention relates to a blower assembly and more particularly to a blower assembly including a pre-swirler for causing air entering the blower assembly to change direction.

BACKGROUND OF THE INVENTION

Centrifugal fans or blowers are commonly used in the automotive, air handling, and ventilation industries for directing a forced flow of air through air conditioning components. In a typical blower assembly, air is drawn into a housing through an inlet aperture by a rotating blower or fan.

Blower assemblies typically include an electrically driven impeller that rotates in a predetermined direction in the housing. The impeller includes one or more curved blades, which draw the air into the impeller axially along an axis of rotation and discharge the air radially outwardly therefrom.

Blower assemblies in automotive applications have been fitted with pre-swirlers to cause a rotation or swirling of air entering the blower assembly. The pre-swirlers cause the air to enter the impeller of the blower assembly at a preferred angle. If the air is not rotated sufficiently, an increase in drag, noise, vibration, and a loss of efficiency of the blower assembly can occur. Accordingly, if the air is pre-rotated and enters the blades of the impeller with a desired amount of rotation, the efficiency of the blower assembly can be maximized.

To overcome the above-described problems, U.S. Pat. No. 3,781,127 discloses a centrifugal blower, which includes a plurality of spin inducing inlet blades and a mechanism for pivotally supporting the blades around an outer wall of an inlet to a centrifugal blower. With this arrangement, an amount of air entering the blower can be controlled and a rotation can be imparted on the incoming air. Alternatively, the blades can be shut completely, thus restricting the flow of air into the blower, while imparting a maximum spin to the incoming air.

While the assembly shown by the '127 patent is effective in varying the amount of air entering the blower, the assembly is costly and complex to manufacture. Furthermore, the assembly requires a mechanism to control an amount of rotation of each of the blades relative to the blower housing, adding further cost and complexity thereto,

It would be desirable to produce a blower assembly that includes a device for rotating a volume of air entering the blower assembly, wherein a cost, an airflow restriction, and a complexity thereof are minimized and an efficiency thereof is maximized.

SUMMARY OF THE INVENTION

Harmonious with the present invention, a blower assembly that includes a device for rotating a volume of air entering the blower assembly, wherein a cost, an airflow restriction, and a complexity thereof are minimized and an efficiency thereof is maximized, has surprisingly been discovered.

In one embodiment, a blower assembly comprises: a blower housing including a fluid inlet and a spaced apart fluid outlet; a fan disposed in the blower housing; and a pre-swirler disposed in the inlet of the blower housing, wherein the preswirler is formed integrally with the blower housing.

In another embodiment, a blower assembly comprises: a blower housing including a fluid inlet and a spaced apart fluid outlet; and a pre-swirler disposed in the inlet of the blower housing, the pre-swirler including a central hub, an outer ring, and a plurality of vanes extending radially outwardly form the hub to terminate at an outer ring.

In another embodiment, a blower assembly comprises: a blower housing including a fluid inlet and a spaced apart fluid outlet; a fan disposed in the blower housing; and a pre-swirler disposed in the inlet of the blower housing, the pre-swirler including a centrally formed hub, an outer ring, and a plurality of vanes, the vanes extending radially outwardly from the centrally formed hub to the outer ring, wherein the vanes include a leading edge, a trailing edge, and a surface formed between the leading edge and the trailing edge, wherein the pre-swirler is formed integrally with the blower housing.

DESCRIPTION OF THE DRAWINGS

The above, as well as other objects and advantages of the invention, will become readily apparent to those skilled in the art from reading the following detailed description of a preferred embodiment of the invention when considered in the light of the accompanying drawings in which:

FIG. 1 is an exploded perspective view of a blower assembly in accordance with an embodiment of the invention;

FIG. 2 is a fragmentary front elevational view of a pre-swirler of the blower assembly illustrated in FIG. 1; and

FIG. 3 is a fragmentary front elevational view of a pre-swirler in accordance with another embodiment of the invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

The following detailed description and appended drawings describe and illustrate various exemplary embodiments of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner.

FIG. 1 shows a blower assembly 10 including a first housing section 12 having a pre-swirler 14 formed therein, a second housing section 16, and a fan wheel 18. The blower assembly 10 is adapted to be disposed in a vehicle (not shown).

The first housing section 12 in the embodiment shown is formed from plastic. It is understood that the first housing section 12 can be formed from other materials as desired. The first housing section 12 includes an inlet aperture 20 and an outlet aperture (not shown) formed therein. The pre-swirler 14 is disposed in the inlet aperture 20. It is understood that the pre-swirler 14 can be formed integrally with the first housing section 12 or separately therefrom as desired. It is also understood that the position of the inlet aperture 20 and the pre-swirler 20 on the first housing section 12 can be moved as desired.

As more clearly shown in FIG. 2, the pre-swirler 14 includes an array of spaced apart vanes 22 extending radially outwardly from a central hub 24. In the embodiment shown, the pre-swirler 14 includes five (5) vanes 22. It is understood that additional or fewer vanes 22 can be used as desired. The vanes 22 extend from the hub 24 to an outer ring 26 that is attached to the first housing section 12. It is understood that if the pre-swirler 14 is formed integrally with the first housing section 12 the outer ring 26 is formed as a part of the first housing section 12. It is noted that the pre-swirler 14 is substantially stationary relative to the first housing section 12. While the outer ring 26 of the pre-swirler 14 shown in FIGS. 1 and 2 is generally circular in shape, it is understood that the pre-swirler 14 can have any shape as desired.

The vanes 22 of the pre-swirler 14 each include a substantially linear leading edge 28 extending along an entire length of the vane 22. The vanes 22 also include a trailing edge 30 spaced from the leading edge 28 and extending radially and axially outwardly from the hub 24 at an angle with respect to the leading edge 28. It is understood that the trailing edge 30 may extend from the hub 24 in other directions as desired. A substantially axially extending outer edge 31 joins the leading edge 28 with the trailing edge 30. The outer edge 31 is a curved or rounded edge, although the outer edge may have other shapes as desired such as linear, for example. It is understood that other configurations can be used as desired, such as wherein the leading edge 28 and the trailing edge 30 merge at a point (not shown) prior to the edges 28, 30 reaching the outer ring 26, for example. The vanes 22 include a first surface 29 and an opposed second surface (not shown) extending from the leading edge 28 to the trailing edge 30. It is understood that the first surface 29 and the second surface can be curved or substantially flat as desired. Spaces 32 are formed between adjacent vanes 22 in the pre-swirler 14.

The second housing section 16 includes an outlet aperture 34 formed therein. Optionally, the second housing section 16 may include an inlet aperture 36 formed therein for receiving a shaft 38 that is mechanically coupled to a motor (not shown). The shaft 38 is also mechanically coupled to the fan wheel 18 to couple the motor to the fan wheel 18.

The first housing section 12 and the second housing section 14 are joined together and cooperate to enclose the fan wheel 18. The fan wheel 18 includes plurality of fan blades 40 disposed around an inlet ring 42 and a hub 44. The outlet aperture of the first housing section 12 and the outlet aperture 34 of the second housing section 16 cooperate to form an air outlet 46 of the blower assembly 10.

In use the fan wheel 18 is driven by the motor and is caused to rotate about an axis of rotation A. The rotation of the fan wheel 18 causes the air to flow through the inlet aperture 20 of the first housing section 12.

The first surfaces 29 of the vanes 22 cause a change of direction of the air in a direction substantially parallel to the first surface 29. It is understood that the second surfaces of the vanes 22 may also cause a change of direction of the air.

Accordingly, the air flows out of the inlet aperture 20 in a different direction than the air entering the inlet aperture 20. Thereafter, the fan wheel 18 causes the air to flow out of the blower assembly 10 through the air outlet 46 to a desired area (not shown).

Since the number of vanes 22 present is less than prior art assemblies, the frictional losses caused by contact between the vanes 22 and the air are minimized. Further, since the blower assembly 10 is simple in structure, a cost and a complexity of manufacture of the blower assembly 10 are minimized. The complexity of the mechanism is minimized since the prior art components necessary to move moveable vanes and a strategy for moving such vanes are not needed by the blower assembly 10 of the present invention. Additionally, to maximize an efficiency of the blower assembly 10, a portion of the air enters the fan wheel 18 traveling radially outwardly. The rotation or change of direction of the air imparted by the vanes 22 of the pre-swirler 14 facilitates the radial outward entry of the air.

It has been found that the blower assembly 10 discussed above for FIGS. 1 and 2 provides an optimal performance for fan wheel speeds of 3200-3400 rpm and airflows of greater than 300 cubic feet per minute (cfm). It should be understood that changing a pitch of the vanes 22 by changing an axial angle of the first surface 29 and changing the number of vanes 22 can both be used to modify a flow restriction and an amount of direction change imparted by the vanes 22. This occurs because a different amount of airflow is influenced by the vanes 22.

FIG. 3 shows a pre-swirler 114 in accordance with another embodiment of the invention. The pre-swirler 114 is adapted to be disposed in an aperture (not shown) of a blower housing (not shown) as discussed above for the pre-swirler 14 shown in FIGS. 1 and 2. The pre-swirler 114 can be formed integrally with or separately from the blower housing as desired.

The pre-swirler 114 includes an array of spaced apart vanes 122 extending radially outwardly from a central hub 124. In the embodiment shown, the pre-swirler 114 includes seven (7) vanes 122. It is understood that additional or fewer vanes 122 can be used as desired.

The vanes 122 extend from the hub 124 to an outer ring 126 that is attached to the blower housing. It is understood that if the pre-swirler 114 is formed integrally with the blower housing, the outer ring 126 is formed as part of blower housing It is noted that the pre-swirler 114 is substantially stationary relative to the blower housing. While the outer ring 126 of the pre-swirler 114 shown in FIG. 3 is generally circular in shape, it is understood that the pre-swirler 114 can have any shape as desired.

The vanes 122 of the pre-swirler 114 each include a substantially linear leading edge 128 extending along an entire length of the vane 122. The vanes 122 also include a trailing edge 130 spaced from the leading edge 128 and extending radially and axially from the hub 124 at an angle with respect to the leading edge 128. The pitch of the vanes 122 shown in FIG. 3 is less than as discussed above for FIGS. 1 and 2. It is understood that the trailing edge 130 may extend from the hub 124 in other directions as desired. A substantially axially extending outer edge 131 joins the leading edge 128 with the trailing edge 130. The outer edge 131 is a curved or rounded edge, although the outer edge 131 may have other shapes as desired such as linear, for example. It is understood that other configurations can be used as desired, such as wherein the leading edge 128 and the trailing edge 130 merge at a point (not shown) prior to the edges 128, 130 reaching the outer ring 126, for example. The vanes 122 include a first surface 129 and an opposed second surface (not shown) extending from the leading edge 128 to the trailing edge 130. It is understood that the first surface 129 and the second surface can be curved or substantially flat as desired. Spaces 132 are formed between adjacent vanes 122 in the pre-swirler 114.

Use of the pre-swirler 114 in a blower assembly (not shown) is similar to that for the pre-swirler 14 described above in FIGS. 1 and 2. The vanes 122 of the pre-swirler 114 cause a change of direction of air entering the blower housing. Since the pitch of the vanes 122 is less than that discussed above for FIGS. 1 and 2, the pre-swirler 114 imparts less rotation on the air entering the blower housing. Further, since the pre-swirler 114 includes more vanes 122 than the pre-swirler 14 discussed above for FIGS. 1 and 2, a larger amount of airflow is influenced by the vanes 122. It has been found that the pre-swirler 114 provides an optimal performance for fan wheel (not shown) speeds of 3000-3200 rpm and airflows of 250-300 cfm.

In the embodiment shown, both the pitch and the number of vanes 122 were modified compared to the pitch and the number of vanes 22 discussed above for FIGS. 1 and 2. It is understood that either of the pitch or the number of vanes 122 can be adjusted independently to optimize performance of the blower assembly for a desired fan wheel speed and a desired airflow range as desired.

While the pre-swirlers 14, 114 have been shown disposed in first blower housing sections 12, 112, it is understood that the pre-swirlers 14, 114 can be used in different types of blower housings as desired, such as a scroll housing, for example, without departing from the spirit and scope of the invention.

From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions. 

1. A blower assembly comprising: a blower housing including a fluid inlet and a spaced apart fluid outlet; a fan disposed in the blower housing; and a pre-swirler disposed in the inlet of the blower housing, wherein the pre-swirler is formed integrally with the blower housing.
 2. The blower assembly according to claim 1, wherein the blower assembly is adapted to be disposed in a vehicle.
 3. The blower assembly according to claim 1, wherein the pre-swirler is substantially stationary relative to the blower housing.
 4. The blower assembly according to claim 1, wherein the pre-swirler includes a plurality of vanes extending radially outwardly form a central hub to terminate at an outer ring.
 5. The blower assembly according to claim 4, wherein the vanes include a leading edge and a trailing edge.
 6. The blower assembly according to claim 5, wherein the vanes include an outer edge extending between the leading edge and the trailing edge.
 7. The blower assembly according to claim 5, wherein the pre-swirler includes five vanes.
 8. The blower assembly according to claim 5, wherein the pre-swirler includes seven vanes.
 9. A blower assembly comprising: a blower housing including a fluid inlet and a spaced apart fluid outlet; and a pre-swirler disposed in the inlet of the blower housing, the pre-swirler including a central hub, an outer ring, and a plurality of vanes extending radially outwardly form the hub to terminate at an outer ring.
 10. The blower assembly according to claim 9, wherein the blower assembly is adapted to be disposed in a vehicle.
 11. The blower assembly according to claim 9, wherein the pre-swirler is formed integrally with the blower housing.
 12. The blower assembly according to claim 9, wherein the pre-swirler is substantially stationary relative to the blower housing.
 13. The blower assembly according to claim 9, wherein the vanes include a leading edge and a trailing edge.
 14. The blower assembly according to claim 13, wherein the vanes include an outer edge extending between the leading edge and the trailing edge.
 15. The blower assembly according to claim 9, wherein the pre-swirler includes five vanes.
 16. The blower assembly according to claim 9, wherein the pre-swirler includes seven vanes.
 17. The blower assembly according to claim 11, further comprising a fan disposed in the blower housing.
 18. A blower assembly comprising: a blower housing including a fluid inlet and a spaced apart fluid outlet; a fan disposed in the blower housing; and a pre-swirler disposed in the inlet of the blower housing, the pre-swirler including a centrally formed hub, an outer ring, and a plurality of vanes, the vanes extending radially outwardly from the centrally formed hub to the outer ring, wherein the vanes include a leading edge, a trailing edge, and a surface formed between the leading edge and the trailing edge, wherein the pre-swirler is formed integrally with the blower housing.
 19. The blower assembly according to claim 18, wherein the pre-swirler includes five vanes.
 20. The blower assembly according to claim 18, wherein the pre-swirler includes seven vanes. 